Analysis of hydrokinetics characteristics in circular impinging stream dryer

In order to study the movement of granular material in impinging stream and the flowing characteristics of material in impinging dryer during drying, a circular impinging stream dryer was designed, and experiments were also carried out with the dryer. Variations of the system pressure-drop versus ratio of material taken were measured. The material velocity variation along its movement direction was analyzed with high-speed photograph camera. Kinetic model of the material was developed, and the material penetration length and its velocity at various positions were calculated. The calculated results agreed well with the experimental results, thus the model can be used to analyze the flowing characteristics in impinging dryer. This model can also be used to obtain parameters, such as accelerating pipe length, the distance between end-faces, mean residence time of particle, etc.. Moreover, the particles vibrated with damping amplitude in the impinging section, and during the first vibration, drying rate was the highest with high relative velocity between the airflow and the particles.